1. Field of the Invention
The present invention relates to a printer of dot impact type, and more particularly, to a dot printer capable of reducing the noise generated when an armature, which supports a print wire of a print head, retreats and collides with a back stopper.
2. Description of Related Art
In the conventional print head used for this type of printer, the armature supporting the print wire is attracted by an electromagnet which extends the print wire to strike a recording paper through an ink ribbon, thereby adhering ink to the recording paper. After striking the paper, and the end of attraction by the electromagnet, the armature rebounds to a "home" position as a result of the impact of striking the paper reinforced by pressure exerted by a spring. The armature's rebound is ended by colliding with a back stopper for holding the armature in the "home" position. In general, a synthetic resin is used as the material for this back stopper.
As shown, for instance, in Japanese Utility Model Laid-Open Publication No.63-63430 and Japanese Utility Model Laid-Open Publication No. 62-187733, a back stopper having a disk shape is used in the conventional print head.
However, in the print head mentioned above, a great deal of noise is generated when the armature collides with the back stopper while printing. This is because the vibration of the back stopper is easily transmitted to the air by the large surface area of the disk shaped back stopper. The majority of the noise is discharged outside of the device without being absorbed or otherwise attenuated. Therefore, there is a problem in that a pleasant environment for using the print device cannot be obtained.